Re: st: Sparse Data Problem

What do you mean when you said "not fully accounting for the small
cell bias"? I don't understand. I thought exact logistic models were
for situations with small cells. -nestreg- does nested estimations for
logit models, though not exact logit models. It was added to Stata in
June of 2008.

-Dave
On Mar 6, 2009, at 9:12 PM, john metcalfe wrote:

Dear Statalist,
I am analyzing a small data set with outcome of interest 'clstr', with
the primary goal of the analysis to determine if the variables 's315t'
and 'east' have independent associations with the outcome. However,
2315t is highly deterministic for the outcome clstr, as below. I am
concerned that exact logistic regression is not fully accounting for
the small cell bias. I would like to employ a hierarchical logistic
regression, but it seems that the stata command 'hireg' is only for
linear linear regressions??
It may be that I simply am unable to make any valid inferences with
this dataset, but I just want to make sure I have explored the
appropriate possible remedies.
Thanks,
John
John Metcalfe, M.D., M.P.H.
University of California, San Francisco
. tab s315 clstr,e
| clstr
s315t | 0 1 | Total
-----------+----------------------+----------
0 | 22 1 | 23
1 | 58 32 | 90
-----------+----------------------+----------
Total | 80 33 | 113
Fisher's exact = 0.002
1-sided Fisher's exact = 0.002
. logit clstr ageat s315t east emb sm num,or
Iteration 0: log likelihood = -62.686946
Iteration 1: log likelihood = -51.860098
Iteration 2: log likelihood = -50.754342
Iteration 3: log likelihood = -50.661741
Iteration 4: log likelihood = -50.660257
Iteration 5: log likelihood = -50.660256